The present invention relates an adjustment device, for example, for adjusting seats.
EP 979 179 discloses a seat adjuster, in which a brake is provided between a fixed part and an adjustable part, to be able to block the two parts continuously in both adjustment directions. The brake can be released via a release element, to then be adjusted in one of the two directions using an adjustment body. An additional locking unit, which acts step-by-step, latches to lock the blocked position. Such latching is perceived to be annoying by the user, since, on the one hand, latching noises occur and on the other hand, latching cannot take place in intermediate positions. In addition, numerous parts are required for the pre-tensioning of the latch, which makes the installation complex.
WO 2012/013234 discloses an adjustment mechanism in which two clamping locks connected in series are provided, where each implements a freewheel brake. The two clamping locks comprise clamping elements, which enable continuous adjustment and blocking in both adjustment directions. The two clamping locks are coupled to one another in this case via a disengagement element, so that after the blocking of an output element by the first clamping lock, the second clamping lock can be switched into a freewheel position, to move an actuating lever back into a starting position. In this case, the actuating lever is pre-tensioned via a first lock spring in a starting position and the disengagement element is pre-tensioned via a second lock spring in a starting position. The two lock springs are arranged in series in the axial direction of the output shaft, so that a relatively large amount of construction space is required in the axial direction. In addition, the problem exists that one lock spring acts on the triggering element and the other lock spring acts on the lever adapter. The reset takes place relatively imprecisely due to tolerances and play.